Patents by Inventor Atsushi Hirashima

Atsushi Hirashima has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Highly water-absorptive ocular lens material
    Patent number: 4920180
    Abstract: A highly water-absorptive ocular lens material obtained by saponification for hydrophilic treatment of a copolymer composed essentially of:(A) from 2 to 30 parts by weight of a (meth)acrylate polymer having at least one polymerizable group per molecule on an average obtained by copolymerizing (a) an alkyl (meth)acrylate monomer and (b) a monomer having at least two polymerizable groups per molecule, as the main components;(B) from 70 to 98% by weight of a fatty acid vinyl ester; and(C) from 0.02 to 3.0 parts by weight of a cross linking agent,provided that the total amount of polymer (A) and monomer (B) is 100 parts by weight.
    Type: Grant
    Filed: March 8, 1989
    Date of Patent: April 24, 1990
    Assignee: Menicon Co., Ltd.
    Inventors: Nobuyuki Toyoshima, Takanori Shibata, Atsushi Hirashima